Intravenous (IV) fluid delivery pumps are used to deliver fluid to a patient or to draw out fluid from a patient's body wherein the patient can be a human or animal. A delivery pump may be, for example, a piston-type pump that drives fluid by moving a piston up-and-down relative to fluid contained in a piston chamber. The pump may further include valve actuators on either side of the piston. The piston and the valve actuators may interface with the piston chamber and inlet-side and outlet-side valves on a disposable cassette. The upward stroke of the piston movement creates a pressure differential that forces fluid out of the piston chamber toward the patient.
Such pumps typically include one or more pressure sensors that measure fluid pressure along a fluid pathway. The valves on the disposable selectively control the flow of fluid into and out of the piston chamber. The valves and the actuators that engage therewith are critical components that are subject to wear and failure. The failure of such valves or actuators can result in large flow rate errors, which can be harmful for a patient, and can also result in other problems related to the delivery of fluid to the patient.
Current systems do not provide for the monitoring of proper valve or actuator function. In view of the foregoing, there is a need for improved systems and devices for monitoring proper valve function in a drug infusion piston pump.